With the standardization of the Ethernet at a higher rate, Ethernet port rates of current electronic devices such as a communication device are evolved from GE (Gigabit Ethernet, Gigabit Ethernet) to 10 GE, 40 GE, and 100 GE. Therefore, higher bandwidth and density requirements are imposed on an Ethernet switching device, and the Ethernet switching device is required to support serdes (parallel-to-serial converter and serial-to-parallel converter) links of higher rates.
A conventional Ethernet switching device generally builds a system based on a serializer/deserializer (serdes) of the rate of 3.125 Gbps or 6.25 Gbps and supports the Gigabit Ethernet (Gigabit Ethernet, GE). After new 10 GE, 40 GE, and 100 GE Ethernet standards are issued, to increase the utilization of physical links, the serdes rates are all evolved to 10.3 Gbps. Therefore, the Ethernet device is required to build a system based on a 10.3 Gbps link.
While supporting the 10.3 Gbps link, there is a strict requirement on the end-to-end cabling length of the system; if the requirement is not met, the operation of the entire link is unstable. Therefore, when the conventional large-scale Ethernet device supports high-speed links, because the cabling on the backplane is too long, the end-to-end serdes link is too long, and the insertion loss is too large, the link cannot work normally. In particular, under a high-temperature environment, if the link is too long, the working state is very unstable.
Based on this situation, to better support high-speed links, the Ethernet device gradually adopts an orthogonal architecture. In the orthogonal architecture, an orthogonal connector is adopted and both sides of the backplane are directly connected to an Ethernet line card and a switching line card, so that the cabling length of the high-speed link on the backplane is reduced to zero. In this way, the end-to-end high-speed link is the shortest, and the insertion loss is the smallest, and the high-speed link of the entire system works stably.
In the orthogonal architecture, although the cabling length of the link is reduced and the system bandwidth is increased, negative impacts are also produced. The largest impact is that the cooling air duct of the system is difficult to design. In particular, the cooling air duct under a specific condition is difficult to design, for example, when the cooling air duct is strictly required with front-air-in and rear-air-out.
Cooling solutions in the prior art are all left-air-in and right-air-out or right-air-in and left-air-out in combination with top-air-in and bottom-air-out or bottom-air-in and top-air-out, and mutually vertical cooling air ducts are adopted. The un-uniform cooling air ducts cause hybrid air flows between the cooling air ducts, and greatly affects the cooling efficiency of the device, thereby increasing power consumption of the device and reducing the reliability of the device.